Means for cooling electric motors.



' J. B WIARD. MEANS FOR COOLING ELECTRIC MOTORS.

APPLIUATION FILED FEB. 23, 1 907 Patented May 4, 1909.

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' referred to may readily be kept unrn snares Parana JOHN B. WIARD, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEYV' YORK.

ZMEANS FOR COOLING- ELECTRIC NZO'IORS.

no. 920,-7es.

Specification-of Letters Patent.

Patented May 4, 1909.

Application filed February 23, 1907. Serial No. 358,768.

bers in the usual way by forcing currents of air between them. This is particularly true in the case or" induction motors having high resistance armature windings.

The object of the present invention is to provide means whereby motors of the type cool.

To the above end Imake the armature'eonductors hollow, that is, in the form of tubes, and provide means for forcing cooling cur rents of air through the interior of these conductors. Thus the cooling medium comes into,direot contact with the surfaces of the parts in which the heat is generated.

The various features of novelty whereb r my invention is characterized will be hereinafter particularly pointed out inthe claims; but for a full understanding of the invention in its various aspects, reference may be had to the following detailed description taken in connection with the accompanying drawing, wherein- Figure 1 is a longitudinal section taken through the axis of an induction motor arranged in accordance .with apreferrred form of my invention; Fig.2 is an end elevation of this motor with a portion of the bonnet broken away so as to more clearly show the end of the armature; and Fig. 3 is a perspective view of the fan or blower which is associated with the armature, parts being broken away to moreclea'rly show the interior construction. 4 j

Referring to the drawing, indicates an induction motor having a primaryor field member 2 and a secondary or armature member 3. The field member may take any usual or preferred form, as may also the armature member except to the extent herein after indicated. The I armature is of the squirrel-oage type having its conductors 4 arranged just within the periphery of the core member 5, and'short-circuited by rings 6 and 7 whi h respectively connect the ends of the conductors together at the ends of shearmature. The armature conductors are made hollow, as shown, and a blower 8 is provided at one end of the armature for producing a continuous flow of air through the interior of these conductors while the'machine remains in operation. The blower may take any usual form, but it is preferably of-the type which forces the air positively through the tubular conductors: it may therefore be made advantageously in the form of a centrifugal blower which receives air at its axis and discharges it at its periphery into and through the tubes.

A convenient method of constructin and supporting the blower consists in utilizingthe end ring 7 as the closed side of the blower.

This ring is therefore made in the form of a disk having a central opening 9 which is not much larger in diameter'than required for the passage of armature shaft. An annular ange 10 projects laterally from the periphery of the disk-like end-ring and, secured to this flange in a plane somewhat removed from the end-ring, is a second disk-like member 11 having a central opening 12 which is larger. 1n diameter than the opening in the member 7 Arranged between the members 7 and 11 are a plurality of radial vanes 13 which extend from the opening 12 to points adjacent the ends of the tubular armature conductors. By this arrangement there is formed at one end of the armature an annular chamber 14 connected to the ends ofthe tubular c0nductors, into which chamber air taken in through the opening 12 of the blower is discharged when the armature begins to rotate. The air" passes from this chamber through the tubular conductors and is discharged at the opposite end of the armature. By properly 'proportioning the parts, the temperature of the motor may be kept within any desired limits. Furthermore, the armature eonductors may be made very thin so as to oii'er extremely high resistance without danger of overheating. What I claim as new and desire .to secure by Letters Patent oi the United States, is, 1. In an induction motor, an armature having hollow conductors, and a blower mounted on said armature in operative rclation to said conductors arranged to force air through the conductors when the motor is in operation.

2. in an induction motor, an armature having hollow conductors, short-circuiting rings at opposite ends of the conductors, and

a blower supported upon one ofsaid rings in position to produce a flow of air through said conductors when the motor is in operation.

3. In an induction motor, an armature having hollow conductors and short-circuiting rings at the ends of the conductors, one of said rings being in the form of a disk, a second disk, and fan blades arranged between the two disks.

4." In an induction motor, an armature having hollow conductors and short-circuiting rings at the ends of the conductors, one of said rings being in the form of a disk, a second disk connected with the short-circuiting disk 50 as to form an annular chamber communicating with the interior of the conduc tors, and radial vanes arranged between said disks.

5. In an induction motor, an armature having hollow conductors and short-circuiting rings at opposite ends of the conductors,

one of said short-circuiting rings being in'the form of'a flanged disk, a second disk connected to the flange of the short-circuiting disk so as to form therewith an inclosing ductors, and radial vanes arranged between i said disks and extending to points adjacent the ends of the conductors.

6. In an induction motor, having hollow conductors, on said armature, having a communicates with the interior of each of the conductors and arranged to an armature JOHN A. MoMANos, J12, HENRY O. WESTENDARP,

tion. l

chamber about the ends of the armature 0011- a blower mounted chamber which forceair through i the conductors when the motor is m'OPQIBr 

